FINAL: manganese Flashcards
food sources of manganese
PINEAPPLE and berries
cereals and grains
nuts
legumes
green leafy vegetables
absorption of Mn via
ZIP14
DMT1
manganese in body exists as
Mn2+ or Mn3+
__% Mn absorption
5% Mn absorption
females absorb __ Mn than males
females absorb more Mn than males
Mn absorption involves __capacity, __ affinity active carrier protein
Mn absorption involves low-capacity, high- affinity active carrier protein
Mn carriers
- DMT1
- ZIP14
- ZIP8
at high Mn intakes,
diffusion occurs
Mn absorption location
small intestine
enhancers of Mn absorption
- low-molecular-weight ligands (histidine and citrate)
inhibitors of Mn absorption
- other divalent cations
- fiber
- phytic acid
- oxalic acid
- iron (competes with DMT1)
- coppuer
Mn absorption steps
- Mn separated from food by HCl, proteases)
- Mn2+ enters via ZIP14 and DMT1
- Ferroportin sends Mn2+ out to blood
3 forms of Mn in portal circulation
- free Mn
- bound to albumin
- oxidized by ceruloplasmin to Mn3+ and complexed with transferrin
within cells, manganese is found primarily as __ in __
within cells, manganese is found primarily as Mn2+ in mitochondria
unlike iron and copper, manganese is not __
unlike iron and copper, manganese is not readily oxidized within tissues
where is manganese found in the body
all organs and tissues (including hair)
manganese highest concentration is within
bone as a part of the apatite
functions of manganese
regulation of cartilage formation
manganese in cartilage formation
enhances __ in growth plates
regulates synthesis of __, a proteoglycan that is essential for cartilage structure
manganese in cartilage formation
enhances osteogenesis in growth plates
regulates synthesis of chondroitin sulfate, a proteoglycan that is essential for cartilage structure
overview functions for manganese
- bone, cartilage, connective tissue synthesis
- urea synthesis
- carb/nutrient metabolism
- amino acid metabolism
- antioxidant roles
excess iron __ manganese absorption
the opposite is true
excess iron inhibits manganese absorption
the opposite is true
homozygous mutations of __ in a cohort of children is associated with clinical hypermanganesemia and progressive parkinsonism-dystonia
homozygous mutations of ZIP14 in a cohort of children is associated with clinical hypermanganesemia and progressive parkinsonism-dystonia
in normal conditions, how much manganese do we lose?
not much at all
main excretion path of manganese
fecal